Edelbrock = 465HP?

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73inNH

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If you review THIS Eddy cam you'll see they claim 465HP / 445ft-lbs. when used with THESE heads and THIS intake manifold.

Cam: $371
Heads: $1,201
Intake: $499
TOTAL: $2,071

So, if I install myself, I can turn my 73 351C 4V into a 465HP tire squealer for just over $2K.

Anyone every try this combo?

P.S. I realize that this stuff is out of stock, and has been for a long time. Still looking for feedback as this seems to be a fairly cheap way to 465HP.
 
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You would need to set the heads up for the cam (as in installing one piece valves, correct springs and a performance valve job), change pistons to raise compression, add headers and 2.5" dual exhaust with free flowing mufflers, and dial in the ignition timing. You will want to consider changing out the rear gear and forget about running power brakes. It will have a fairly snotty idle and the carb idle and transition circuits will probably need some modification as well. For street/strip car it might be ok. For a cruiser it isn't a good choice IMO.
 
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EDIT: Sorry I read the 351C 4V as you using the factory heads. It didn't register that you were including the Eddy heads. The rest still applies.
 

73inNH

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What TommyK said....

That's $1200 per head, so add $1200 to your total.

You should explain your goals a bit.
Ahhh . . . Didn't notice the per head. Thanks for pointing that out.

I don't have lofty goals, just more power. :) Currently have 650 carb, 2.5 dual, Eddy intake, 73 351 4v heads.

I'd like to fix the potential stock valve issue with my current heads and like the lightweight aluminum thought . . .
 

Mister 4x4

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I too wanted more power than the factory offered, and since I had to rebuild my engine from seized, I threw the check book at it. Your engine isn't too far off of mine, and I'm pushing around 406 at the crank. My recipe:
  • Original 351 Cleveland 2V worked over by a local machine shop
    - Balanced, Blueprinted, Magnafluxed
    - Bored .060"
    - 3-angle valve job, mild port & polish
  • Edelbrock Performer intake
  • Edelbrock 1406 Performer 600CFM carb
  • Holley electric fuel pump
  • CompCams High-Energy 270/270 @ .566" roller cam
  • CompCams High-Energy lifters & pushrods
  • CompCams High-Energy 1.73 roller rockers
  • Crane Cams 7/16" screw-in rocker studs
  • Keith Black 9.5:1 hypereutectic flat-top pistons
  • Duraspark II ignition and distributor
  • Accel Super-Coil & 8mm wires
  • Hooker Competition ceramic-coated headers
  • Pypes Street Pro mufflers
  • Pypes 2.5" stainless exhaust with 'X' pipe
  • Pypes 2.5" chrome 'slash' tips
The cam and 1.73 roller rockers made the most difference, but everything else contributed, with the 9.5:1 pistons helping immensely as well. I have 3.00 rear gears and have no issues getting a burn-out, while still enjoying cruising the freeway around 1800 rpm (with an AOD transmission, that is). I also have the factory 2V heads (which most probably think I'm weird not wanting 4V heads, but I'm quite happy with them).

As the others mentioned, what exactly does 'More Power' mean to you? There are no wrong answers, but depending on what you want the car to do, you might not even need to crack open the engine itself to get there. Maybe a rear gear change, if you have cruising gears like I do, can get you off the line a lot quicker if that's what you need (but kill your top end).

That entire list above ran me about $7K in 2012 money, BTW. A quick look on JEGS, and the cam kit, roller rockers, screw-in rocker studs, pistons, and Duraspark ignition system would probably run in that $2000-ish range, and with what you currently have, would probably get you in that 400HP range as well. Leave out the pistons, and you've saved around $400 and still increased horsepower by over 100 from the factory... and haven't pulled the main rotating mass from the engine. How deep into this are you willing to go?

Hope this helps.
 

73inNH

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I too wanted more power than the factory offered, and since I had to rebuild my engine from seized, I threw the check book at it. Your engine isn't too far off of mine, and I'm pushing around 406 at the crank. My recipe:
  • Original 351 Cleveland 2V worked over by a local machine shop
    - Balanced, Blueprinted, Magnafluxed
    - Bored .060"
    - 3-angle valve job, mild port & polish
  • Edelbrock Performer intake
  • Edelbrock 1406 Performer 600CFM carb
  • Holley electric fuel pump
  • CompCams High-Energy 270/270 @ .566" roller cam
  • CompCams High-Energy lifters & pushrods
  • CompCams High-Energy 1.73 roller rockers
  • Crane Cams 7/16" screw-in rocker studs
  • Keith Black 9.5:1 hypereutectic flat-top pistons
  • Duraspark II ignition and distributor
  • Accel Super-Coil & 8mm wires
  • Hooker Competition ceramic-coated headers
  • Pypes Street Pro mufflers
  • Pypes 2.5" stainless exhaust with 'X' pipe
  • Pypes 2.5" chrome 'slash' tips
The cam and 1.73 roller rockers made the most difference, but everything else contributed, with the 9.5:1 pistons helping immensely as well. I have 3.00 rear gears and have no issues getting a burn-out, while still enjoying cruising the freeway around 1800 rpm (with an AOD transmission, that is). I also have the factory 2V heads (which most probably think I'm weird not wanting 4V heads, but I'm quite happy with them).

As the others mentioned, what exactly does 'More Power' mean to you? There are no wrong answers, but depending on what you want the car to do, you might not even need to crack open the engine itself to get there. Maybe a rear gear change, if you have cruising gears like I do, can get you off the line a lot quicker if that's what you need (but kill your top end).

That entire list above ran me about $7K in 2012 money, BTW. A quick look on JEGS, and the cam kit, roller rockers, screw-in rocker studs, pistons, and Duraspark ignition system would probably run in that $2000-ish range, and with what you currently have, would probably get you in that 400HP range as well. Leave out the pistons, and you've saved around $400 and still increased horsepower by over 100 from the factory... and haven't pulled the main rotating mass from the engine. How deep into this are you willing to go?

Hope this helps.
Sounds like a nice build!

$7k (or $9k prob with inflation (is more than I'm going to spend. I'll keep researching. :)
 
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How many miles are on your engine? If the cylinders, pistons and rings and the rods, crank and bearings are worn throwing more power on the top end will likely result in failure of something else, possibly destroying the block. Horsepower can be cheap, longevity costs more.
 

Mister 4x4

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Sounds like a nice build!

$7k (or $9k prob with inflation (is more than I'm going to spend. I'll keep researching. :)
Read all the way to the bottom of my post - you could probably get pretty close to what I have for around $2K with just a cam kit, pistons, roller rockers, and ignition system upgrade (assuming you don't already have something like an MSD or similar). $3500 of my cost was from the machine shop's work, including fitting up the pistons, cam bearings, boring, balancing, et al. You already have some of the other big money items I also had to buy at the time (carb, intake, exhaust system, etc.), so you're already part way there. I just checked on those things via JEGS before I posted the reply. ;)
 
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I would not doubt that Edelbrock combo could make 465 HP. Here is a dyno test of what Richard Holdener describes as a stock M-Code 351 C and what he got with just a cam and intake swap. Stock with headers he said he got 365 HP, and with a 240/246 cam at .050 and an Edelbrock intake he got 450 HP. This is with stock cast iron closed chamber 4V heads. He used pistons with a small dome that would give him a real 11:1 compression ratio, as far as I know the M-code pistons were flat, and even though the engine was rated as 10.7 to 11:1 compression, the real compression was closer to 10:1. So, the "stock 365 hp" is probably 20-30 hp higher than with a stock piston:

Here is another dyno test with a 351 C with stock 4V heads and stock valvetrain, 406HP, they then change to Edelbrock heads with roller rockers and got 430HP. Edelbrock heads with aluminum roller rockers only made 24 HP more than stock 4V heads, remember the roller rockers had to be at least 5 HP out of those 24HP, to me the Edelbrock heads are not worth the $2500 investment for maybe 20HP. This engine eventually ended up at 450 with the Edelbrock heads:


If you have some good 4V closed chamber heads, making 400 hp out of a 351 Cleveland is only a little compression, an intake, headers, and a good healthy street cam away. 450hp is just a bigger cam away, lol. That 240/246 cam that Holdener used is not exactly a very streetable cam.
 

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I'd be hesitant to just throw heads and a cam on any engine that's 50 years old. I would at least hone, new rings, replace cam bearings as they are prone to wear/failure, inspect crank and turn as needed. If the bores are good, you can get a set of KB flat tops for around $300 and have them installed on the rods. New Clevite 77 bearings, some ARP nuts for the rod bolts, a couple of Tim Meyer's oiling system tricks and you're good to go.


At that point, with the 4V OC heads, you have a 9.0:1 engine and have not spent a bunch. Have the heads rebuilt with Ferrea valves and springs/retainers appropriate for the cam.

Another option is the Trick Flow 195 heads. Less than the Edelbrock and a better head, which will put you at 10.6:1 compression with the 60cc version. Use the Edelbrock intake and get a custom ground cam to match the intake and heads.


Pics below are from a post on the Cleveland FB group, guy used stock 4V OC heads. The cam might be a bit lumpy, but the torque production is impressive.

351cjspecs.JPG

121615773_10157923343625432_1238766786299845915_o.jpg
 

73inNH

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OK - excellent info here. I'll give this a bit more thought.

I still like the idea of dropping the cast iron weight with aluminum heads, but a small part of me feels like I lose the "Cleveland Mystique" if I lose the heads. This will be a Winter project so I guess I have some time.

Thanks everyone for the ongoing thoughts!!
 
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Similar to what 71ProjectJunk and Hemikiller have posted, there was someone from the Clevelands Forever group that posted their dyno sheet for a version of the Edelbrock config using ported iron 4v head, so those power values are realistic.

I agree with what has been said about using the bottom end as is. I recall having customers insist that they only wanted a valve job or to fix a blown head gasket. Soon after that work, many of those engines would smoke and burn more oil than they did before the work. I surmised the additional pressure had taken their toll on worn rings or they had overheated and softened the rings. Plan on refreshing the bottom and don't be surprised if you find the scope of your project creeping....it always does.
 
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OK - excellent info here. I'll give this a bit more thought.

I still like the idea of dropping the cast iron weight with aluminum heads, but a small part of me feels like I lose the "Cleveland Mystique" if I lose the heads. This will be a Winter project so I guess I have some time.

Thanks everyone for the ongoing thoughts!!
Nothing at all "controversial" about your head, cam and intake swap. Work with a trusted supplier/builder for appropriate part numbers. The power improvements will be dramatic compared to the antiquated 50 year old parts. My suggestion before building top end is to run a compression and leakdown test to help verify bottom end health. If power your after, 450+ hp reliable Cleveland is not rocket science. Your on the right track.
 
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Any 351 C with any of the OEM iron 4V heads, even the open chamber type, can easily make 400 hp with just a cam, intake/carb, and headers as long as we have a good serviceable short block. The only caveat is the compression ratio of the open chamber heads with stock pistons. If you can get into a real 9.5 to 10:1 compression you are golden. The Cleveland is not like the Windsor engines, the heads flow a bunch of air, and making power is not that difficult.
 

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Any 351 C with any of the OEM iron 4V heads, even the open chamber type, can easily make 400 hp with just a cam, intake/carb, and headers as long as we have a good serviceable short block. The only caveat is the compression ratio of the open chamber heads with stock pistons. If you can get into a real 9.5 to 10:1 compression you are golden. The Cleveland is not like the Windsor engines, the heads flow a bunch of air, and making power is not that difficult.
That's why I mentioned getting some KB Hypereutectic 9.5:1 flat tops (like mine), along with the cam kit, roller rockers, screw-in 7/16" rocker studs, and updating the ignition system (if necessary). With his intake, carb, and exhaust, he pretty much has my engine at that point (although 4V heads vice my 2V heads), and that would be a solid 400hp (at the crank) for less than the $2k he had originally mentioned wanting to spend.
 

73inNH

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That's why I mentioned getting some KB Hypereutectic 9.5:1 flat tops (like mine), along with the cam kit, roller rockers, screw-in 7/16" rocker studs, and updating the ignition system (if necessary). With his intake, carb, and exhaust, he pretty much has my engine at that point (although 4V heads vice my 2V heads), and that would be a solid 400hp (at the crank) for less than the $2k he had originally mentioned wanting to spend.
I upgraded to a Pertronix Flamethrower II disty and ignition a while back. Just adding more info. : )

In my head, I'm a bolt on guy. I've never bolted on heads, but I feel like I can. Again, in my head, the thought of changing pistons seems like a huge job. Maybe it's not. Just some insight into the psyche of a bolt-on guy. :)

I will do a compression test this week or this weekend and post numbers, to add some data.
 
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Bolting on heads is a relatively simple job, that can be done in a day, as long as you thoroughly clean all the mating surfaces and torque everything to spec by the book. If you have a stock valvetrain it will be much simpler, if you have an adjustable valvetrain it will be a bit more involved, as you need to adjust the rockers one by one, but doing that is still fairly simple.
Now, changing pistons is a different story, you can remove and disassemble your engine at home, check the cylinders to see if they are still round, or round enough and within specs, give it a quick hone and throw some new gaskets, oil pump, bearings, timing chain, pistons and piston rings at it, but it is a much more involved job. Definitely not an afternoon job, and a job that really needs to be done slowly and meticulously. If it is your first time doing something like that, the best thing is to get a friend that has done it before to help guide you, or read a lot about it, look at a ton of videos, and ask a lot of questions, and if at some point you are not sure, stop and ask questions.
 

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As he mentioned, the pistons are quite a bit more involved, and almost turn into one of those "while you're at it" kind of projects. If you pull the pistons, you're wise to pull the crank and replace all the main & con rod bearings... which means pulling the engine. While you're at it, take it to a machine shop and make sure it all gets mic'd and adjusted as needed to ensure consistency - they could go through the block and machine anything needing adjustment, install the cam bearing and pistons to the con rods, and match the pistons and bearings to anything they need to make bigger. So yeah, swapping pistons is a bit involved, but I was focusing on getting to the magic 9.5:1 compression ratio.

All of the bolt-ons will definitely get more power, but without upping the compression ratio, you'll have a tough road getting to the 400+ number you're wanting.
 

73inNH

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Let me throw a curveball . . . . I'm going to assume my heads need to be rebuilt. I'm not aware of any issues but I know the valves are a weak spot and the springs are likely tired etc. If I stay the cast-iron head route and don't go to aluminum:

1. Can I rebuild these heads with common DIY guy knowledge? I have a lift so I do a LOT myself, but I'm never opened an engine, aside from changing an intake.

2. Is there a good tutorial you trust?

3. Would anyone be able to put together a decent 351C 4V Head Rebuild shopping list? I'd prefer to upgrade rather than just replace.

4. I don't have the ability to mill, but if necessary to raise compression, I could have it done.

Thoughts? : )
 
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